Abstract:Combined molecular and morphological analyses demonstrate that a number of small-flowered Caribbean Asclepiadoideae of hitherto uncertain affiliation form two independent lineages in Asclepiadeae – Gonolobinae, and
not, as previously assumed, in the Metastelmatinae. One lineage is described as the new genus Anemotrochus, which
includes the widespread Caribbean A. eggersii, a species originally described under Metastelma; A. yamanigueyensis,
a new species discovered by the authors in E Cuba; and A. viridivenius, a plant from Hispaniola formerly assigned to
Matelea. The second lineage, Tylodontia, is a small genus restricted to Cuba. Besides its type species, T. cubensis, the
genus comprises T. fuscula, a species formerly assigned to Metastelma; T. stipitata, a new species described here; and
T. urceolata, a species formerly assigned to Astephanus. Anemotrochus and Tylodontia belong to the wider Matelea alliance, but they form endemic Antillean, mainly Cuban lineages independent from Matelea. All species, except for A. viridivenius, are fully described and illustrated, and distribution maps are provided. The names Metastelma
eggersii and Astephanus schlechterianus (a synonym of T. fuscula) are lectotypified here.